标题：The tunability of the electronic structures for poly(carbosilylsilanes): A theoretical study
作者：Ding, Y.;Feng, S.;Sun, X.;Diao, S.;Yang, Z.;Xu, Q.;Liang, Y.;Wang, X.;Jin, K.
作者机构：[Ding, Y] Key Laboratory of Special Functional Aggregated Materials, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong Uni 更多
通讯作者地址：[Feng, SY]Shandong Univ, Minist Educ, Sch Chem & Chem Engn, Key Lab Special Funct Aggregated Mat, Jinan 250100, Peoples R China.
关键词：Conformation;DFT;Poly(carbosilylsilanes);Spectral properties;Substituent effect
摘要：To tune purposefully the electronic structures of poly(carbosilylsilanes), a theory study has been investigated using the density functional theory combined with AM1 method. Attentions were paid to the dependence of molecular geometries and absorption spectra on the backbone conformation and the various substituting groups. The strong electronegative substituents can more effectively tune the geometries and spectra of the polysilanes than the alkyl ones. Their main-chain substitutions can induce the great red-shift of the absorption spectra, and the side-chain substitutions can induce the blue-shift. The length of methylene chain in the carbosilyl groups exerts the small effect on the absorption spectra, but with the lengthening of side chain, poly(carbosilylsilanes) have a preference for the all-trans conformation with the loose helix backbone. Different from the alkyl side chain in poly(alkylsilanes), the lengthening of carbosilyl chain leads to the decrease of the positive charges of silicon backbone.